John fisher



( No Model.)

J FISHER SIGNAL WIRE GOMPBNSATOR.

N0.f506,106. Patented 00 3, 1893.

NITED STATES PATENT QFFICE.

JOHN FISHER, OF MATLOOK, ENGLAND.

SIGNAL-WIRE COM PENSATOR.

SPECIFICATION forming part of Letters Patent No. 506,106, dated October3, 189 3. Application filed February 4, 1893. Serial No, 461,024.. (Nomodel.) I

To all whom it may cancer-m Be it known that I, JOHN FISHER, gentleman,a subject of the Queen of Great Britain, residing at Matlock, in thecounty of Derby, England, have invented an Improved Apparatus forKeeping Constantly Stretched the Wires Used for Actuating Signals uponRailways and for other Purposes of the Like Kind, of which the followingis a specification.

My invention relates'to the wires used for actuating semaphore or othermechanical signals situated at considerable distances from the pointwhere the sigualman is sit-uated. Such wires are liable to vary inlength by fluctuations in temperature, by the strain upon them and fromother causes, and attempts have been made to provide means forautomatically compensating such variations in length and for keeping thewires uniformly stretched, but such attempts have not hitherto beensuccessful, and the object of my improvement is to insure the signalwires being kept properly stretched, and being automatically connectedto the signalmans lever when the latter is being. used and automaticallydisconnected from the lever when it is out of use, without thepossibility of failure. I attain this object by the mechanismillustrated in the accompanying drawings, in which Figure 1 is a sideview of the entire apparatus; Fig. 2 a top view of the same; and Figs. 3and 4E detailed views of the chain wheel and friction bar in dilferentpositions, and Figs. 5 and 6 show further details on an enlarged scale.

Similar letters refer to similar parts in the different views.

In such apparatus it is necessary that the wire which extends from thelever actuated by the signalman to the distant semaphore or other signalwhich remains normally in the position indicating danger should be keptpermanently and uniformly stretched while in such position, and for thispurpose the wire after passing over a pulley at the signalmans stationhas suspended to it a weight sufficiently heavy to keep it properlystretched under all circumstances but not sufficient to prevent thegreater weight at the distant signal from raising it when the latter isbrought to the position indicating danger. In this position the leverworked by the Signalman is practically disconnected from the wire, butwhen he moves the lever over for the purpose of lowering the signal fromthe danger position, it becomes automatically connected with the wirewhich is therefore pulled with sufficient force to raise thesignalweight and lower the signal. When on the other hand the lever is broughtback the wire is also brought back and the signal returns to the dangerposition, the wire being then freed so that the weight suspended to itkeeps it properly stretched in spite of variations of temperature orother causes tending to alter its effective length.

Itis necessary that the apparatus should be absolutely reliable andincapable of getting out of order and this I effect by my presentinvention.

f is a horizontal lever turning upon a pivot r at or near the center ofits length supported in fixed bearings d. This lever f is made double(as shown in Fig. 2) the two sides being parallel but at a shortdistance apart, and at the outer end is arranged a pulley I) turng im erings in the lever, overwhich pulley a chain c is passed, the lower endof the chain passing down and under a fixed pulley 1011 Sh Wn in thedrawings) and being connected to the end usual Way. Upon the center 1"on which the lever is pivoted as described, and between the two parallelsides of the latter is fitted a pulley a which can revolve freelyindependently of the lever. This pulley is grooved at its circumferencewith a groove of such shape as to receive the chain 6 which passes overit from the pulley b, without the possibility of the chain slipping inthe groove. The end of the chain epassing down from the grooved pulley ahas attached to it a weight i suffi ciently heavy stretched and theinner end of the lever f is provided with an adjustable weight g. Thelever is also connected toa vertical or other rod 0 (shown broken off)communicating with the ordinary signal-mans lever or handle. It isevident that if the last named lever or handle be now pulled over, theouter end of the pivoted lever f will be raised without altering theposition of the signal wire, but if the grooved chain pulley a be firstrigidly to keep the .wire properly of the signal wire in the attached tothe pivoted lever f, then when the handle is pulled the pulley a will beturned with the lever and will draw the chain c with it, the signal wirebeing also pulled and the distant signal being thereby lowered, thestretching weight 2' suspended from the end of the chain also descendingfor a corresponding distance.

For the purpose of connecting and disconnecting the grooved pulley afrom the pivoted leverfat the right times and with absolute certaintyand freedom from risk of failure, I makelthe bearings d in which thepivot r of the leverfand grooved pulley a turns sufficiently elongatedvertically (as shown in Fig. 1) so that it together with the leverf andpulley at can rise for a short distance, and to the lever I attach asemi-circular or curved bar Z which passes round under the lower side ofthe pulley at, its ends being pivoted to theleverf at m and a betweenthe two sides of the latter, and the hole through which the pivot at oneof its ends passes being also somewhat elongated vertically as shown aton, so that it can rise and fall for a short distance, the curve of thelower side of the bar Z being such that when raised it is concentricwith the pulley a. This lower side of the bar rests upon a frictionroller h turning in bearings below the pulley, which bearings may bemade adjustable.

Upon the upper side of the curved barZ below the pulley a is a frictionblock or brake atp having teeth which fit into similar teeth made roundthe flange of the wheel a. The lowercurved bar Z which carries thefriction block is made of less depth at and near its outer end so thatwhen the pivoted lever is in its normal position (as shown in Figs. 1and 3) such reduced part rests upon the friction roller h below, thefriction block or brakep being clear of the pulley, and the centralpivot r of the lever fand pulley a rests upon its bearings. When howeverthe signal handle is pulled over the outer end of the leverf is raisedand the enlarged part of the curved bar Z comes upon the friction rollerit below (as shown in Fig. 1) the friction block 1) being forced againstthe pulleya and the latter together with the pivoted leverf being raisedsomewhat from their bearings so that their whole weight forces thepulley a against the brake block.

As the movement of the handle is contin ued the wheel a locked asdescribed to the lever f by the brake block 19 is turned with the latterand draws the chain c with it, the lower enlarged concentric part of thecurved bar Z moving over the friction roller h (as illustrated in Fig.4) and slipping or failure being impossible. hen thehandle is broughtback it brings the pulley a with it, until the reduced part of thecurved bar Z reaches the friction roller h when the brake block 19 isreleased, the pulley a and pivoted lever f return to their bearings, andthe former is free to revolve and to allow the weight '11 to keep thewire stretched. The curved bar Zhas an opening through which the chain 6passes to the weighty An adjustable screw, as shown at .9 may be made toinsure the release of the brake block 13.

' In order to prevent lateral play and to reduce friction, I preferablymake the pivots of the pulleys of such length that they do not projectbeyond the bearings in which they turn, and I fit and attach platesoutside the latter (as shown at b in Figs. 1 and 2, and on an enlargedscale in Fig. 6) which effectually prevent any lateral play of thepivots and reduce friction.

The bearings of the pivot 7" may be pro vided with plates of a similarkind formed upon the covers of the bearings, as shown at (Z in Figs. 1,2, and 5.

Instead of teeth round the flange ofthepulley a, they maybe made roundaseparate wheel or disk attached to the pulley a. The teeth upon thepulley and upon the brake 19 may be made of any suitable shape to givesufficient adhesion between the pulley and the brake.

What I claim, and desire to secure by Letters Patent of the UnitedStates,is

1. In apparatus for actuating signals, the combination of the level-f,loose chain wheel a, vertically elongated bearings cZ, curved bar Zpivoted at n, and movable vertically on pivot m, friction rollerh, chain6, and weight 'Z, ar-

ranged and operating substantially as and for the purpose described andillustrated in Figs. 1, 2, 3, and 4.

2. In combination with the curved bar Z, loose pulley a, and elongatedbearipgs d, the friction block or brake, substantially as described andillustrated in Figs. 1, 3, and 4.

3. In combination with the leverf, and pulleys a, Z), the plates Z), CZ,against which the ends of the pivots bear, substantially as and for thepurpose described and illustrated in Figs. 1, 2, 5, and 6.

In testimony whereof I have hereunto set my hand in the presence of twosubscribing witnesses.

JOHN FISHER.

Witnesses:

EDMUND EDWARDS, ARTHUR ERNEST EDWARDS.

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